La Trobe Uni research shows cardioprotective qualities of olive oil

New research shows consuming extra virgin olive oil every day can significantly reduce blood pressure, which is a key risk factor for cardiovascular disease.

Researchers say the project is significant because it’s the first Australian study to show a drop in central systolic blood pressure (in central arteries such as the aorta) and peripheral systolic blood pressure (in smaller arteries in the arm) linked to olive oil consumption.

The study, led by La Trobe University and published in  Nutrients, is also important because it involved participants from many cultural backgrounds – showing that Mediterranean heritage is not a factor in benefiting from olive oil consumption.

The researchers led a clinical trial into the cardioprotective qualities of extra virgin olive oil, produced in Australia, in 50 healthy adults with diverse backgrounds and dietary habits.

They found consuming four tablespoons of extra virgin olive oil per day can reduce central and peripheral systolic blood pressure by 2.5 and 2 per cent, respectively.

Lead author and La Trobe PhD candidate Katerina Sarapis said understanding how olive oil consumption impacts multi-ethnic communities is important.

“Extra virgin olive oil is rich in a variety of active compounds such as polyphenols, which have proven health benefits thanks to their anti-inflammatory and antioxidant properties,” Sarapis said.

“This popular oil is widely recognised as a nutritious source of dietary fat when paired with traditional, Mediterranean style diets from Greece and Spain. Our study confirms the benefits associated with olive oil consumption extends to people without Mediterranean heritage but who have different cultural upbringings, traditions and food preferences.”

The trial compared the effects of extra virgin olive oil with refined low polyphenol olive oil.

“We asked participants to add 60 millilitres – or 4 tablespoons – of either extra virgin or refined olive oil to their daily diets for three weeks. Following a two-week break where participants could not eat olive oil or olives, they were then asked to consume the alternative oil,” Sarapis said.

The researchers measured blood pressure after each three-week period.

“The refined, low polyphenol olive oil had no significant impacts on blood pressure, but the extra virgin olive oil caused a reduction in central and peripheral systolic blood pressure. This is of clinical importance, as this result was achieved without the use of any blood pressure medications,” Ms Sarapis said.

Primary supervisor of the collaborative PhD project, La Trobe Associate Professor George Moschonis, said the study is an important step forward in heart disease prevention.

“Cardiovascular disease is the leading cause of death globally. Our findings provide evidence for a potentially widely accessible dietary intervention that can reduce cardiovascular risk in populations not accustomed to a high consumption of extra virgin olive oil,” Associate Professor Moschonis said.

The study was led by La Trobe with collaborating academics at Swinburne University of Technology, Bond University, Deakin University and Murdoch University.

Eating organic foods lowers rates of cancer, research shows

A new study has indicated there could be correlation between organically grown foods and lower rates of cancer.

The research, published by JAMA Internal Medicine in late-October, was part of the French NutriNet-Sante study, which included almost 70,000 volunteers who were free of cancer.

At the beginning of the study, each participants’ diet was assessed based on the French nutritional guidelines and their food and drink consumption recorded in three 24-hour snapshots over two weeks.

Two months into the study, the participants were asked to provide specific information about their consumption of 16 categories of organically labelled foods.

READ: Booming Australian organics industry finding a unified voice

This included fruits, vegetables, soy-based products, dairy products, meat and fish.

The participants were then given an organic food score. If they chose organically produced foods in all 16 categories, they would get a maximum score of 32.

The health of each participant was assessed each year and monitored for a median period of 4.5 years.

When any cases of cancer occurred, details were independently confirmed with the individual’s hospital or treating physician.

The participants’ organic food scores ranged from 0.7 to 19.4. These were used to divide the group into equal quartiles.

The overall cancer risk was 25 per cent lower in those who had the highest organic food score.

Cancers showing the greatest correlation with decreased risk were breast cancer – especially in postmenopausal women, and lymphomas – especially non-Hodgkin’s lymphoma.

No correlation appeared with prostate or colorectal cancers, although the relatively short time frame would have made any change unlikely.

But, while there was a correlation between eating organic foods and lower rates of cancer, it doesn’t necessarily mean one caused the other.

People who choose organic foods are likely to be healthier, wealthier and better educated, all factors known to impact risk of cancer, the study explains.

Researchers note that this is the first study of its kind so the findings need to be confirmed in other studies before organic food can be proposed as a preventive strategy against cancer.

However, past research has found that higher intakes of fruit, vegetables and wholegrains – however they are grown – and lower intakes of processed and red meats can decrease the risk of cancer.

As previous studies with this group had shown people who choose organically grown products tend to have higher income, higher levels of education and healthier diets.

So the researchers adjusted for these factors.

They also made adjustments for other factors that could affect the outcome, such as age, sex, the month the participants were included in the program, marital status, physical activity, smoking status, alcohol intake, family history of cancer, body mass index, height, energy intake, and the intake of dietary fibre and also red and processed meat.

For women (who made up 78 per cent of the study group), they also adjusted for the number of children they had, oral contraception use, postmenopausal status and use of hormonal treatment for menopause.

In 2015, the International Agency for Research on Cancer classified some pesticides as “probably carcinogenic to humans”.

This means there is limited evidence of a link between pesticide use and cancer in humans, but sufficient evidence of a link between pesticide use and cancer in experimental animal studies.

 

Monash University researches why people find some foods disgusting

The thought of consuming an insect-based snack bar or smoothie as part of a staple diet could make even those with the strongest of stomachs squirm. Monash University researchers try to find out why.

They are trying to understand why the ‘disgust’ mechanism of the brain prevents people from trying foreign foods that actually possess health benefits – in this case, insects.

Professor Eugene Chan from Monash Business School’s Department of Marketing conducted two separate studies into the link between the state-of-mind and emotional reaction to newly-introduced foods.

The results were published in the international scientific journal, Food Quality and Preference.

READ: Monash University professor recognised for 30-year study to bring millions worldwide safe water supply

The first study measured the willingness of 202 participants to try five different insect-based products, from deep-fried silkworms and crickets, to chocolate chip cookies that were baked with cricket flour.

In the second study, 155 participants were presented with two drinks with identical positive health benefits – but one was a by-product of silkworm protein and the other from ordinary cow’s milk.

Participants in both studies were subjected to mindfulness exercises – including guided meditation, breathing training and listening to a 15-minute audio track that induced a mind-wandering state – and had never consumed insects previously.

“Despite being presented with the positive health and environmental benefits as motivational factors to choose insects as a viable food and nutrition source, we found that participants reacted with disgust and instead opted for the more ‘familiar’ food source,” said Chan.

“These findings were completely opposite to my initial expectations. Entomophagy (the consumption of insects) is not a new practice and has been taking place for tens of thousands of years. More than two billion people world-wide regularly eat insects as part of their diet and there are more than 2000 edible insect species.

“I anticipated that mindfulness might have encouraged people to try insects as it removes some of that initial negative reaction to a foreign food. Perhaps disgust is an emotion that is too negative and powerful to influence a behaviour change,” said Chan.

Chan’s research also found that the role of disgust in food choice is not just restricted to eating insects. It also includes trying new foods or cuisines that are an intrinsic part of a culture foreign to one’s own.

“Blue vein cheese, which is characterised by mouldy spots and a foul odour, may be present at many social functions and the family dinner table which could please some people but disgust others. Even being presented with offal and unfamiliar fruit and vegetables could enliven our ‘disgust’ mechanism – despite the contents being perfectly edible,” Professor Chan said.

“While this research only focuses on testing the impacts of mindfulness on a person’s willingness to try insect-based foods, it is possible that increased self-awareness might produce different – perhaps even positive – reactions towards actually eating insects.

“Although our attitudes towards insect eating is generally negative, individuals who actually try insect-based foods may respond more favourably than their initial attitudes predict,” said Chan.

Mindfulness, commonly associated with Buddhism, refers to the state of being aware and taking note of what is going on within oneself and the outside world.

International studies have shown that mindfulness can deliver positive eating behaviour by treating various eating disorders and altering consumption patterns.

Research helps towards creating more stable brewing processes

New findings from University of Adelaide researchers, could help provide more stable brewing processes or new malts for craft brewers.

The researchers discovered a link between one of the key enzymes involved in malt production for brewing and a specific tissue layer within the barley grain.

The most important malting enzymes come from a layer of tissue in the barley grain called the aleurone, a health-promoting tissue full of minerals, antioxidants and dietary fibre.

The research showed that the more aleurone present in the barley grain, the more enzyme activity the grain produced.

READ: Aussie blockchain startup BlockGrain to pilot barley-to-beer tracking

Barley is the second most important cereal crop for South Australia and contributes over $2.5 billion to the national economy. This is largely due to its use in beverage production.

University of Adelaide school of agriculture, food and wine associate professor and project leader, Matthew Tucker, said barley grains had impressive features ideal for creating the malt required by the brewing industry.

“During the malting process, complex sugars within the barley grain are broken down by enzymes to produce free sugars, which are then used by yeast for fermentation. The levels of these enzymes, how they function and where they are synthesised within the barley grain are therefore of significant interest for the brewing industry,” he said.

“Until now, it was not known that this key ingredient in the beer brewing process was influenced by the amount of aleurone within the grain, or that the aleurone was potentially a storage site for the enzyme,” said Tucker.

The researchers examined the aleurone in a range of barley cultivars used by growers and breeding programs in Australia and found remarkable variation in the aleurone layer between varieties.

Tucker said breeders and geneticists could make use of this natural variation to select for barley varieties with different amounts of aleurone and different malting characteristics.

“This will be of potential interest to large brewers who depend on stable and predictable production of malt, and also the craft brewers that seek different malts to produce beer with varying characteristics.”

PhD student Matthew Aubert used the variation to examine levels of enzymes involved in malt production.

He discovered that barley grains possessing more aleurone had noticeably more activity in one of the key enzymes that breaks down starch and determines malt quality of barley, an enzyme called free beta-amylase.

Aubert said grains with more aleurone could have an advantage that allowed them to break down complex sugars faster or more thoroughly than grains with less aleurone.

The researchers are now trying to find the genes that explain this natural variation.

Aubert’s research was supported by the Australian Research Council Centre of Excellence in plant cell walls and the Grains Research and Development Corporation.

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